Lesson 2:Density

Density is a property of matter that shows a relationship

between mass and volume.

It measures the amount of

matter in a certain space.

An object or substance with a low density will have less mass than a more dense object with the same

volume.

Cotton Ball Iron Ball

less dense than

Discovery Education Video:Density: The Relationship Between Mass and Volume

An object’s density can be calculated if we know it’s

mass and volume.

Density is measured using the unit grams per cubic

centimeter (g/cc).

To calculate density, we divide the object’s mass by the object’s volume

A golf ball has a mass of 45 grams and a volume of

40 cubic centimeters

Density = Mass ÷ VolumeDensity = 45 ÷ 40

Density = 1.13 g/cc

Water has a density of 1 g/cc.

An object with a density less than

1 g/cc will float, but an object with a

density more than 1 g/cc will sink.

Buoyancy is the ability of an object to float in water.

Key Questions:1) What does density measure? How is it related to mass and volume?2) How can we measure the density of an object?3) What makes an object buoyant in water? How does this relate to the object’s density?